Strue

: : : : : ==It was like we became friends first, that's the honest to god truth"?

: : : : : thank you

: : : : The crucial phrase is, I think, 'Honest to God', rather than 'God truth'. It is reasonably common I think, and derives, presumably, from the speaker asking God to validate the truth of the statement - swearing an oath, if you like:

: : : : 'That is the truth, honest to God,' might be another way of saying it.

: : : : DFG

: : : It would be clearer if the original author had punctuated it " that's the honest-to-god truth" ... the hyphens connecting the three words would show them as an adjective modifying "truth."

: ..and hence the erstwhile Cockney but now predominantly Australian abbreviation "strewth", which is a member of the "cor blimey", "crikey", "bloody" and, more archaically, "zounds" and "gadzooks" euphemistic family.